1 files changed, 147 insertions, 0 deletions
diff --git a/nuttx/arch/arm/src/common/up_checkstack.c b/nuttx/arch/arm/src/common/up_checkstack.c
new file mode 100644
index 000000000..27ac20234
--- /dev/null
+++ b/nuttx/arch/arm/src/common/up_checkstack.c
@@ -0,0 +1,147 @@
+/****************************************************************************
+ * arch/arm/src/common/up_checkstack.c
+ *
+ *   Copyright (C) 2011 Gregory Nutt. All rights reserved.
+ *   Author: Gregory Nutt <spudmonkey@racsa.co.cr>
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ * 3. Neither the name NuttX nor the names of its contributors may be
+ *    used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+ * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ *
+ ****************************************************************************/
+
+/****************************************************************************
+ * Included Files
+ ****************************************************************************/
+
+#include <nuttx/config.h>
+
+#include <sys/types.h>
+#include <stdint.h>
+#include <sched.h>
+#include <debug.h>
+
+#include <nuttx/arch.h> 
+
+#include "os_internal.h"
+
+#if defined(CONFIG_DEBUG) && defined(CONFIG_DEBUG_STACK)
+
+/****************************************************************************
+ * Private Types
+ ****************************************************************************/
+
+/****************************************************************************
+ * Private Function Prototypes
+ ****************************************************************************/
+
+/****************************************************************************
+ * Global Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Name: up_check_stack
+ *
+ * Description:
+ *   Determine (approximately) how much stack has been used be searching the
+ *   stack memory for a high water mark.  That is, the deepest level of the
+ *   stack that clobbered some recognizable marker in the stack memory.
+ *
+ * Input Parameters:
+ *   None
+ *
+ * Returned value:
+ *   The estimated amount of stack space used.
+ *
+ ****************************************************************************/
+
+size_t up_check_tcbstack(FAR _TCB *tcb)
+{
+  FAR uint32_t *ptr;
+  size_t mark;
+
+  /* The ARM uses a push-down stack:  the stack grows toward lower addresses
+   * in memory.  We need to start at the lowest address in the stack memory
+   * allocation and search to higher addresses.  The first word we encounter
+   * that does not have the magic value is the high water mark.
+   */
+
+  for (ptr = (FAR uint32_t *)tcb->stack_alloc_ptr, mark = tcb->adj_stack_size/4;
+       *ptr == 0xDEADBEEF && mark > 0;
+       ptr++, mark--);
+
+  /* If the stack is completely used, then this might mean that the stack
+   * overflowed from above (meaning that the stack is too small), or may
+   * have been overwritten from below meaning that some other stack or data
+   * structure overflowed.
+   *
+   * If you see returned values saying that the entire stack is being used
+   * then enable the following logic to see it there are unused areas in the
+   * middle of the stack.
+   */
+
+#if 0
+  if (mark + 16 > tcb->adj_stack_size)
+    {
+      int i, j;
+
+      ptr = (FAR uint32_t *)tcb->stack_alloc_ptr;
+      for (i = 0; i < tcb->adj_stack_size; i += 4*64)
+        {
+          for (j = 0; j < 64; j++)
+            {
+              int ch;
+              if (*ptr++ == 0xDEADBEEF)
+                {
+                  ch = '.';
+                }
+              else
+                {
+                  ch = 'X';
+                }
+              up_putc(ch);
+             }
+          up_putc('\n');
+        }
+     }
+#endif
+
+  /* Return our guess about how much stack space was used */
+
+  return mark*4;
+}
+
+size_t up_check_stack(void)
+{
+  return up_check_tcbstack((FAR _TCB*)g_readytorun.head);
+}
+
+size_t up_check_stack_remain(void)
+{
+  return ((FAR _TCB*)g_readytorun.head)->adj_stack_size - up_check_tcbstack((FAR _TCB*)g_readytorun.head);
+}
+
+#endif /* CONFIG_DEBUG && CONFIG_DEBUG_STACK */